miller



(No Model.) 2 Sheets-Sheet 1.

F. MILLER. FRICTION CLUTCH.

N H j i I WITNESSES. i 1 C Z INVENTCIR. mw

(No Model.) 2 Sheets-Sheet 2. F- MILLER. FRICTION CLUTCH.

Patented Feb. 9, 1892.

Fi qB.

V 'm m UNITED STATES PATENT OFFICE.

FRAN K. MILLER, OF CLEVELAND, OHIO, ASSIGNOR TO JACOB B. PERKINS, OF

' SAME PLACE.

FRICTION-CLUTCH.

SPECIFICATION forming part of Letters Patent No. 468,626, dated February9, 1892. Application filed March 11, 1889. Serial No. 302,795. (Nomodel.

To aZZ whom it may concern.-

"Be it known that I, FRANK. MILLER, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented certain new and useful Improvements in Friction-Clutches, ofwhich the following is a full, clear, and exact description, referencebeing had to the aocompanying drawings.

:0 My invention is designed particularly to apply to that class offriction-clutches in which a cylindric pulley-flange is grasped betweentwo inversely and radially moving jaws.

Among the objects of my invention are,

first, to provide novel mechanism whereby the aws are caused to movesimultaneously toward the interposed pulley-flange for the purpose ofgrasping the same between them; second, to provide novel mechanismwhereby two inversely and radially moving jaws are caused to movesimultaneously and positively both toward and from the interposedpulleyflange for the purpose, first, of grasping, and, second, ofreleasing, said flange third, to

provide novel adjusting mechanism to compensate for wear and to permitthe jaws to grasp pulley-flanges of different thicknesses, and also tosimplify and improve the construction and mode of operation offriction-clutches,

as herein described.

My invention consists in the combination of a pair of clutch members ofthe type specified with a pivoted wedge block having a curved-wedge armadapted to engage with 3 5 the jaw-shanks, and thereby compel both jawsor friction-surfaces to simultaneously move toward and grasp theinterposed flange; sec 0nd, in the combination of a pair of clutchmembers of the type specified with a pivoted o wedge-block having twocurved-wedge arms which engage between the jaw-shanks at two points, andthereby alternately move the jaws 'or friction-surfaces simultaneouslyand positively toward or away from the flange; third,

5 in the combination, with a pair of radiallymoving clutch members andpivoted wedgeblock having a curved-wedge arm to engage with thejaw-shanks, and thereby cause the jaws to move simultaneously in inversedirections with a shifting sleeve and an adj ustable connection betweensaid shifting sleeve and wedge.

It further consists in the special features and subordinate details ofconstruction hereinafter described, and definitely pointed out in theclaims. 7

I will now proceed to describe the embodiments of my inventionillustrated in the drawings.

In said drawings, Figure l is a side elevation of my improved clutchmechanism with so much thereof removed as is below the line 1 1 onFig.2. Fig. 2 is a central sectional view on the line 2 2 of'Fig. 1.Fig. 3 is a plan view of the outer clutch member. Fig. 4 is a plan viewof the inner clutch member. Fig. 5 is a central sectional view throughboth clutehmembers when they are in operating position. Fig. 6 is anenlarged sectional view taken on the line 6 6 on Fig. 2, and Fig. 7 is atransverse sectional view of the clutch-arm at a point near the inneredge of yoke 0.

Referring to the parts by letters, A represents a shaft, and B a pulleymounted thereon, having the oylindric pulley-flange b. C represents ahub, keyed or otherwise secured upon said shaft, and from this hubradiate as many arms as there are clutch systems. This hub and its armsconstitute what will be herein termed a clutch-frame. Upon thisclutch-frame are provided radial guides for the shanks of the clutchmembers.

In the form of the invention shown each of the radial clutch-armsconsists of two parallel bars 0, which are connected, preferably, by ayoke c. The proximate faces of these bars are provided with grooves 0which serve as the guides above named.

D represents the outer and E the inner clutch member. Each of theseclutch memo bers consists of an inwardly-projecting shank (Z and (2,respectively, and an overhanging jaw or friction-surface d and e,respectively, the outer friction-surface being concave and the innerfriction-surface being convex. In these general characteristics theclutch members are substantially like the clutch members commonly usedin this style of clutch. The jaw-shanks of each of the clutch membersare provided with longitudinal slots (1 I00 block G and the lever Ntogether.

6 respectively, through which the wedge hereinafter referred to passes.

d d represent pins, which are fastened to the outer jaw-shank in anysuitable manner, and in a position, when the parts are assembled, atright angles to a radial plane. c (2 represent similar pins similarlysecured to the jaw-shank of the inner clutch member. These pins 61 d c care so arranged that when the parts are assembled they will all lie inthe same plane, and their ends, which project on both sides of theshanks to which they are attached, will lie in the grooves c in theclutch-arms, whereby the jaws will be held in their proper position andbe guided in radial paths without the necessity of smoothly finishingthe entire edges of the shanks, as would be necessary if said edges,instead of the pins, engaged in the grooves in the clutch-arms.

G represents a wedge-block having two curved-wedge arms g g and havingthe arm 9 projecting midway between the two wedgearms 9' g?. This arm gis pivoted to the clutch-arm by means of a pin g which lies between thepins d d and in line therewith. One of the curved wedges g is insertedbetween the pin a and the pin (2 while the other curved wedge g isinserted between the pins 01 6 so that when the said wedge-block isoscillated in one direction upon its pivot it will drive the wedge gbetween two pins d e and force them apart, and thereby move the two jawsor friction-surfaces toward each other and toward the interposedpulley-flange, and when oscillated in the other direction the wedge g iswithdrawn, and at the same time and to the same extent the wedge g isdriven between the pins 61 6, thereby forcing said pins apart anddrawing the two jaws away from each other and from the interposedpulley-flange.

N represents a slotted leve which straddles the wedge-block G and ispivoted to the same pivot-pin 9 The outer periphery of the wedge-blockbetween the two curved-wedge arms g g is in the form of the arc of acircle of which its axis of oscillation is the center. Upon theouteredge of this part of the wedgeblock G a rack g is formed and a wormH is mounted in the lever N and engages with said rack, therebyconnecting the wedge- A curved slot g is cut in the wedge G, and a pin apasses through this slot and through both parts of the lever N andserves as-a pivot by which the link I is secured to said. lever N. Theother end of the link I is pivoted to a suitable shifting sleeve J. Theshifting sleeve J may be of any suitable form and it may be adapted toslide either upon the hub O or upon the shaft. In the constructionshown, however, the shifting sleeve has one part j, which slides uponthe shaft, and the arms 3'', which extend over the hubs (3, and have thelugs 7' which slide upon the hub. The hub has the shoulders 0 againstwhich the lugs j strike when the clutch is locked, and the shoulders 0,against which said lugs strike when the sleeve has been drawn back farenough to completely release the clutch. In order that this shiftingsleeve may reach the position shown in Fig. 2. the shoulder c is cutaway between the points where the lugs 7' engage with it when inoperative position, so that said sleeve may be slipped over the hub andthen given about an eighth of a turn,which prevents it from beingslipped off again.

When the parts are assembled in the manner hereinbefore described, andshown in the drawings, it operates as follows: WVhen the shifting sleeveis moved backward from the locked position shown block G is rocked sothat the curved wedge g is withdrawn from and the curved wedge g drivenin between the pins, with which they engage respectively, therebycausing both jaws to move simultaneously from the flange b. When thesleeve is moved in the opposite direction, the curved wedge g iswithdrawn from and the curved wedge g simultaneouslyinserted between thepins with which they engage respectively, thereby moving the jaws towardeach other and firmly gripping the flange b. As the jaws become worn thewedges are adjusted by the turning of the worm H, so that the lever Nconnects with the wedgeblock at a pointnearer the wedge g If greataccuracy is required in the operation of the clutch, a small plate K isinserted between the worm and the outer end of the lever N, and when theparts are properly adj usted this plate is thrust against the worm bymeans of a set-screw 7r,therebypreserving the adjustment until such timeas is desired to change the same.

I do not wish to be understood as limiting my invention to thesubordinate details of construction herein shown and described furtherthan is expressed distinctly in the claims. The clutch in its entirety,as herein shown, is the best and most complete embodiment now known tome of my invention in all its details; but one skilled in the clutch artwill readily see how these details may be varied in many ways withoutdeparting from the principle of the invention and without discardingsome of its essential parts.

Among the modifications which will suggest themselves may be mentionedchanges in the form of the clutch-arm, in the details of the j aw-shanksand the means for seating them on the clutch-frame, the employment of awedge-block having only one curved-wedge arm instead of two, in theadjusting devices, in the form and arrangement of the shifting sleeve,and in the connections between said wedgeblock and shifting sleeve.

I hereby disclaim as my invention, first, the combination, in afriction-clutch, of a pulley having a cylindric flange, a radialclutch-arm, and two inversely and radially moving clutch members of thetype specified,

in Fig. 2, the wedgei for said wedge, a shifting sleeve,

with a movable wedge adapted to engage with the shanks of said clutchmembers; second, the combination, in a friction-clutch, of a pulleyhaving a cylindric flange, a radial clutclbarm, and two inversely andradially moving clutch members of the type specified, with a movablewedge adapted to engage with the shanks of said members, a shiftingsleeve, suitable connections between said sleeve and wedge, and meansfor guiding the movement of said wedge; third, the combination, in afriction-clutch, of a pulley having a cylindric flange, a radialclutch-arm, and two inversely and radially moving clutch members of thetype specified, the inner ends of the shanks of the two members being insubstantially the same radial plane with a wedge, guides and anadjustable connection between said wedge and shifting sleeve, and,fourth, the combination of a pulley having a cylindric flange and twoinversely and radially movable clutch members with a clutch-armconsisting of two parallel bars having grooves upon their proximatefaces in which the shanks of the clutch members slide, and mechanism formoving said clutch members.

In comparison with the combinations above enumerated my claims arespecific claims and are limited to some specific form or mode ofoperation of one or more of the elements named in said combinations orcontain some new limiting element in addition thereto.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a friction-clutch, the combination of a pair of clutch members ofthe general type specified and a clutch-frame upon which they aremounted with a wedge-block pivoted to said frame and having twocurved-wedge arms on opposite sides of the pivotal point, adapted toengage with the shanks of said clutch members, substantially as and forthe purpose specified.

2. In a friction-clutch, the combination of an oscillating wedge-blockadapted to operate the clutch members of the friction-clutch and aclutch-frame to which said wedge-block is pivoted with a lever pivotedto said frame upon the same center, a rack-and-worm connection betweensaid lever and wedge-block, a shifting sleeve, and suitable connectionsbetween said shifting sleeve and lever, substantially as and for thepurpose specified.

In a friction-clutch, the combination of a radial clutch-arm consistingof two parallel grooved bars and a pair of clutch members of the typespecified, each clutch member having two pins projecting from both sidesof its shank and engaging at their ends in said grooves, with mechanismfor imparting to said clutch members a simultaneous inversemovement,substantially as and for the purpose specified.

4. In a friction-clutch, the combination of a pair of clutch members ofthe general type specified, having their shanks slotted longitudinall yand transverse pins extending across said slots and projecting from thesides of the shanks, and a clutch-arm consisting of two parallel groovedside bars, with an oscillating wedge-block pivoted to said side bars andhaving a curved-wedge arm which engages with a pin on each of saidshanks,substantially as and for the purpose specified.

5. In a friction-clutch, the combination of a pair of clutch members ofthe general type specified, each having slotted shanks and twotransverse pins and a clutchframe upon which said shanks are seated,with a wedgeblock pivoted to said frame and having two curved-wedge armsand a curved slot, a lever pivoted to said frame upon the. same center,a worm-and-rack connection between said lever and wedge-block, a pinpassing through said curved slot and secured to said lever, a linkpivoted to said lever by said pin, and a shifting sleeve, substantiallyas and for the purpose specified.

6. In a friction-clutch, a wedge-block for operating the clutch members,having an arm g, whereby said block is pivoted, and two curved wedges gg on opposite sides of said arm, the outer periphery of said wedge-blockbetween the two wedges being curved in the arc of a circle of which thewedge-block pivot is the center and having a rack formed on the saidcurved edge, substantially as and for the purpose specified.

7. In a friction-clutch, the combination of a pair of clutch members ofthe general type specified, having slotted shanks and a clutchframe uponwhich said shanks are seated, with a wedge-block G, pivoted to saidframe and having a curved-wedge arm g, a lever N, pivoted to said frameon the same center, a curved rack on said wedge-block, a worm H, mountedin said lever, a movable block K, set-screw It), a shifting sleeve, andconnections between said lever and shifting sleeve, substantially as andfor the purpose specified.

FRANK. MILLER.

Witnesses:

E. L. THURSTON, W. J. BAINBRIDGE.

